1. Field of the Invention
The present invention relates to an electrodeless discharge lamp and particularly, to a bulb with a reflector and an electrodeless discharge lamp using the same, capable of emitting light in a bulb where inert gas is sealed using microwave.
2. Description of the Background Art
An electrodeless discharge lamp is a kind of a lamp including a bulb in which appropriate amount of inert gases, such as Argon and the like are sealed so that light is emitted under the plasma condition by exciting with microwave. Such electrodeless discharge lamp has longer life span than that of an incandescent lamp or fluorescent lamp which is generally used and has higher lighting effect.
FIG. 1 is a longitudinal sectional view showing a conventional electrodeless discharge lamp. As shown in the drawing, the conventional electrodeless discharge lamp includes a case 1, a magnetron 3 positioned inside the case 1, for outputting microwave, a waveguide 5 installed in the case 1, for transmitting the microwave outputted from the magnetron 3, a bulb 7 positioned and protruded outwards from the front side of the case 1, in which inert gas G is sealed, for emitting light, a resonator 19 fixed at the outlet port of the waveguide 5, formed in a mesh structure, to block microwave and pass light, and a reflector 11 fixed on the front side of the case around the resonator 19, for reflecting light emitted from the bulb 7 to the front thereof.
At the inner side of the case 1, a high voltage generator 13 is positioned to supply a power with a high voltage.
In the waveguide 5, a shaft hole 5a is formed at the center portion and a rotational shaft 10 which can rotate the bulb 7 passes into the shaft hole 5a. A bulb motor 9 combined with the rotational shaft 10 is installed at the bottom of the waveguide 5 to cool the bulb 7 by rotating the bulb.
On the other hand, a cooling unit 14 is installed in the rear portion of the case 1 to cool the magnetron 3 and the high voltage generator 13. The cooling unit 14 includes a fan housing 17 which is a passage through which outside air flows into the case, a cooling fan 15 positioned in the fan housing 17 and a fan motor 16 for driving and rotating the cooling fan.
On the other hand, an inner side surface of the reflector 11 is formed as a reflective face to reflect light emitted from the bulb 7 forwards and a reflecting mirror 12 is installed to reflect light emitted from the bulb 7 to the side of waveguide 5 at the outlet of the waveguide 5.
However, the conventional electrodeless discharge lamp has problems that much time is taken to manufacture and assemble the lamp and the whole size becomes larger since the conventional electrodeless discharge lamp is assembled by respectively manufacturing the reflector 11, reflecting mirror 12, bulb 7 and resonator 19.
Due to the above problems, the conventional electrodeless discharge lamp can not be applied to low power systems, namely, to a liquid crystal projector, projection television and the like as a power source, which require a compact composition as a light source, since the size of the lamp is increased by the size of the reflector 11 and assembly structure, even though it has longer life span than that of the incandescent lamp or fluorescent lamp which is generally used and has higher lighting effect.
To solve the above problem of the conventional art, the present invention provides a bulb with a reflector and an electrodeless discharge lamp using the same capable of reducing assembly time of the bulb and reflector and the size of the lamp by forming the bulb where inert gas is sealed and reflector for integrally reflecting light.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided an electrodeless discharge lamp in accordance with the present invention, including a waveguide for transmitting a microwave generated in a magnetron, a resonator installed at an outlet port of the waveguide, for blocking the microwave and passing light and a united bulb, formed with a bulb portion sealing inert gas, for emitting light by the microwave and a reflective portion for integrally reflecting light emitted from the bulb portion forwards, which is positioned inside the resonator.
At least a part of the resonator is formed in a mesh structure so that the light emitted from the united bulb is emitted to the outside.
The resonator includes a non-mesh portion, formed in a cylindrical structure with both sides opened, which is fixed to the outlet of the waveguide and a mesh portion installed at an opened portion of a side of the non-mesh portion, for passing light emitted from the united bulb.
The united bulb is connected with a bulb motor, which is fixed with the resonator, by a rotational shaft and is cooled by rotating.
An injection hole of the united bulb is formed on a side and a packing member seals the injection hole.
The waveguide is assembled in a case and the outlet port is protruded out of the case.
The magnetron is fixed on the side surface of the waveguide in the case.
A high voltage generator for supplying a raised high voltage to the magnetron is installed in the case.
A cooling unit is positioned at one side of the case to cool the magnetron and high voltage generator.
The bulb with a reflector for an electrodeless discharge lamp in accordance with the present invention to achieve the above object, includes a bulb portion in which inert gas is sealed and a reflective portion extended integrally from a side of the bulb portion and a reflective face in at least one part to reflect the light emitted from the bulb portion.
The united bulb and reflective portion are formed with a material that the microwave can penetrate and an injection hole is formed on a side of the united bulb and a packing member seals the injection hole.
In accordance with an embodiment of the present invention, a cross-section of the reflective portion is formed in a parabolic structure and the bulb portion is formed to be positioned at the focus of the reflective face.
The bulb portion is formed in the globular shape and integrally connected to the reflective portion by the connection portion.
In accordance with another embodiment of the present invention, a side surface of the reflective portion is formed in a semicircular structure and the bulb portion is formed in the globular shape and integrally connected to the inner central surface of the reflective portion.
In accordance with still another embodiment of the present invention, the reflective portion is formed in a flat surface structure and the bulb portion is formed in the globular shape, positioned a certain distance apart from the reflective portion and integrally connected to the reflective portion by the connection portion.
The foregoing and other, features, aspects and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.